OBJECTIVES We assessed relationships between indoor black carbon (BC) exposure and urinary oxidative stress biomarkers, 8-hydroxy-2'-deoxyguanosine (8-OHdG) and malondialdehyde (MDA), in participants with chronic obstructive pulmonary disease (COPD). METHODS Eighty-two participants completed in-home air sampling for one week prior to providing urine samples up to four times in a year. Weekly indoor and daily outdoor concentrations were used to estimate indoor daily lags and moving averages. There were no reported in-home BC sources, thus indoor levels closely represented outdoor BC infiltration. Mixed effects regression models with a random intercept for each participant were used to assess relationships between indoor BC and 8-OHdG and MDA, adjusting for age, race, BMI, diabetes, heart disease, season, time of urine collection, urine creatinine, and outdoor humidity and temperature. RESULTS There were positive effects of BC on 8-OHdG and MDA, with the greatest effect the day before urine collection (6.9% increase; 95% CI 0.9-13.3%, per interquartile range: 0.22 μg/m3) for 8-OHdG and 1 to 4 days before collection (8.3% increase; 95% CI 0.03-17.3% per IQR) for MDA. Results were similar in models adjusting for PM2.5 not associated with BC and NO2 (10.4% increase, 95% CI: 3.5-17.9 for 8-OHdG; 8.1% increase, 95% CI: -1.1-18.1 for MDA). Effects on 8-OHdG were greater in obese participants. CONCLUSIONS We found positive associations between BC exposure and 8-OHdG and MDA, in which associations with 8-OHdG were stronger in obese participants. These results suggest that exposure to low levels of traffic-related pollution results in lipid peroxidation and oxidative DNA damage in individuals with COPD.

中文翻译：

---

慢性阻塞性肺疾病患者的室外室内黑碳和氧化应激生物标志物。

目的我们评估了慢性阻塞性肺疾病（COPD）参与者的室内黑碳（BC）暴露与尿液氧化应激生物标志物，8-羟基-2'-脱氧鸟苷（8-OHdG）和丙二醛（MDA）之间的关系。方法82位参与者完成了一周的室内空气采样，然后每年进行多达四次的尿液采样。使用每周的室内和室外每日浓度来估计室内的每日滞后时间和移动平均值。尚无家庭内BC的报道，因此室内水平密切代表了室外BC的渗入。使用每个参与者随机截距的混合效应回归模型评估室内BC与8-OHdG和MDA之间的关系，并调整年龄，种族，BMI，糖尿病，心脏病，季节，尿液收集时间，尿肌酐，以及室外湿度和温度。结果BC对8-OHdG和MDA有积极影响，在尿液收集的前一天，对8-OHdG和MDA的影响最大（增加6.9％； 95％CI 0.9-13.3％，每个四分位范围：0.22μg/ m3）。 MDA收集前1至4天（增加8.3％；每个IQR 95％CI 0.03-17.3％）。在调整不与BC和NO2无关的PM2.5的模型中，结果相似（8-OHdG增加10.4％，95％CI：3.5-17.9； MDA增加8.1％，95％CI：-1.1-18.1）。肥胖参与者对8-OHdG的影响更大。结论我们发现BC暴露与8-OHdG和MDA之间呈正相关，其中肥胖参与者中与8-OHdG的关联更强。